Freescale MMA845xQ系列三轴加速度计开发方案

Freescale MMA845xQ 系列三轴加速度计开发方案系列三轴加速度计开发方案 关键字 工业控制 传感器 电子罗盘 Freescale 公司的 MMA845xQ 系列是智能低功耗三轴容性微机械加速度计 具 有 12 位分辨率 电源电压 1 95V 3 6V 接口电压 1 6V 3 6V 动态可选择满刻度 2g 4g 8g 输出数据速率 ODR 为 1 56 Hz 到 800 Hz 12 位和 8 位数字输 出 I2C 数字输出接口 电流消耗 6uA 160uA 主要用于电子罗盘 静态方向检测 笔 记本 电子书等跌落检测 实时方向检测和工作分析 手持设备运动检测 震动和振 动监视和用户接口 本文介绍了 MMA845xQ 系列主要特性和方框图 应用框图以 及 MMA845xQ 加速计开发套件 LFSTBEB845x 电路图与 MMA8451 2 3Q 应用 电路图 The MMA8452Q is a smart low power three axis capacitive micromachined accelerometer with 12 bits of resolution This accelerometer is packed with embedded functions with flexible user programmable options configurable to two interrupt pins Embedded interrupt functions allow for overall power savings relieving the host processor from continuously polling data The MMA8452Q has user selectable full scales of 2g 4g 8g with high pass filter filtered data as well as non filtered data available real time The device can be configured to generate inertial wakeup interrupt signals from any combination of the configurable embedded functions allowing the MMA8452Q to monitor events and remain in a low power mode during periods of inactivity The MMA8452Q is available in a 3 mm by 3 mm by 1 mm QFN package MMA845xQ 系列主要特性 1 95V to 3 6V supply voltage 1 6V to 3 6V interface voltage 2g 4g 8g dynamically selectable full scale Output Data Rates ODR from 1 56 Hz to 800 Hz 99 ug Hz noise 12 bit and 8 bit digital output I2C digital output interface Two programmable interrupt pins for six interrupt sources Three embedded channels of motion detection Freefall or Motion Detection 1 channel Pulse Detection 1 channel Transient Detection 1 channel Orientation Portrait Landscape detection with set hysteresis Automatic ODR change for Auto WAKE and return to SLEEP High Pass Filter Data available real time Self Test RoHS compliant Current Consumption 6uA 165 uA MMA845xQ 系列典型应用 eCompass applications Static orientation detection Portrait Landscape Up Down Left Right Back Front position identification Notebook eReader and Laptop Tumble and Freefall Detection Real time orientation detection virtual reality and gaming 3D user position feedback Real time activity analysis pedometer step counting freefall drop detection for HDD dead reckoning GPS backup Motion detection for portable product power saving Auto SLEEP and Auto WAKE for cell phone PDA GPS gaming Shock and vibration monitoring mechatronic compensation shipping and warranty usage logging User interface menu scrolling by orientation change pulse detection for button replacement 图 1 MMA845xQ 系列框图 图 2 MMA845xQ 系列应用框图 MMA845xQ 加速计开发套件 The Freescale MMA845xQ sensor toolbox accelerometer kit provides hardware and software for development and demonstration of the MMA845xQ family of accelerometers MMA845xQ 加速计开发套件包括 The kit includes the following MMA845xQ evaluation board MMA8451Q accelerometer daughter board MMA8452Q accelerometer daughter board MMA8453Q accelerometer daughter board The kit requires the LFSTBUSB USB interface board to attach the kit to a personal computer If you already have the RD3924MM450Q Sensor Toolbox for the MMA8450Q accelerometer the USB board is in that kit The MMA845xQ kit s part number is LFSTBEB845x and the USB interface board s part number is LFSTBUS